Installation guide

2.2.2.1
Using the Console Port ..................................... 2–7
2.2.2.1.1
Turning Off Console Log Messages .................. 2–7
2.2.2.1.2
Shutting Down the Remote System ................. 2–8
2.2.2.1.3
Ending a Remote Session ............................. 2–8
2.2.3
Troubleshooting .................................................. 2–8
3 Starting Up and Shutting Down the System
3.1
Understanding the Boot Operation ................................ 3–1
3.2
Preparing to Boot Installed System ............................... 3–3
3.2.1
Preparing to Boot a Powered-Down System ................. 3–3
3.2.2
Preparing to Boot a Powered-Up, Halted System .......... 3–4
3.2.3
Preparing to Transition from Single-User Mode ........... 3–5
3.2.4
Preparing to Boot a Crashed System ......................... 3–5
3.3
Booting the System ...................................................
3–6
3.3.1
Defining Console Environment Variables and Using Boot
Commands ........................................................
3–6
3.3.2
Overriding Boot Commands .................................... 3–10
3.4
Identifying System Run Levels ..................................... 3–10
3.5
Changing System Run Levels ...................................... 3–11
3.5.1
Changing Run Levels from Single-User Mode .............. 3–11
3.5.2
Changing Run Levels from Multiuser Mode ................ 3–12
3.5.2.1
Changing to a Different Multiuser Run Level ......... 3–12
3.5.2.2
Changing to Single-User Mode ........................... 3–12
3.5.2.3
Reexamining the inittab File .............................. 3–13
3.6
Symmetric Multiprocessing ......................................... 3–13
3.6.1
Adding CPUs to an Existing System ......................... 3–14
3.6.2
Unattended Reboots on Multiprocessor Systems ........... 3–14
3.7
Setting and Resetting the System Clock ......................... 3–14
3.8
Resolving Booting Problems ........................................ 3–15
3.9
Shutting Down the System ......................................... 3–16
3.10
Stopping Systems While in Multiuser Mode ..................... 3–17
3.10.1
Shutting Down the System and Warning Other Users .... 3–17
3.10.2
Shutting Down and Halting the System ..................... 3–18
3.10.3
Shutting Down and Automatically Rebooting the System 3–18
3.10.4
Shutting Down and Halting Systems Immediately ........ 3–19
3.11
Stopping Systems While in Single-User Mode .................. 3–19
4 Customizing the System Environment
4.1
Identifying and Modifying System Initialization Files ......... 4–1
4.1.1
Using the /etc/inittab File ...................................... 4–4
4.1.1.1
Specifying the Initialization Default Run Level ....... 4–6
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